Where did you install Firefox from? Help Mozilla uncover 3rd party websites that offer problematic Firefox installation by taking part in our campaign. There will be swag, and you'll be featured in our blog if you manage to report at least 10 valid reports!

Rechercher dans l’assistance

Évitez les escroqueries à l’assistance. Nous ne vous demanderons jamais d’appeler ou d’envoyer un SMS à un numéro de téléphone ou de partager des informations personnelles. Veuillez signaler toute activité suspecte en utilisant l’option « Signaler un abus ».

Learn More

How to downgrade a Firefox install on old iMac (late 2009) when I can't open browser?

  • 1 réponse
  • 0 a ce problème
  • 1 vue
  • Dernière réponse par cor-el

more options

Hi, the turbotax website forced me to update Firefox and since I did, I am no longer able to open the browser at all. The error message reads, "You can't use this version of the application "Firefox" with this version of OS X. You have OS X 10.11.6. The application requires OS X 10.12 or later." Unfortunately, from what I have read, I can't get that update that on my iMac (21.5inch, late 2009) OS X El Capitan Version 10.11.6. Is there any way to downgrade the Firefox install? I can't even see what previous version of Firefox I had before because I can't open the browser anymore. If anyone can help I would be super grateful. Thanks in advance!

Hi, the turbotax website forced me to update Firefox and since I did, I am no longer able to open the browser at all. The error message reads, "You can't use this version of the application "Firefox" with this version of OS X. You have OS X 10.11.6. The application requires OS X 10.12 or later." Unfortunately, from what I have read, I can't get that update that on my iMac (21.5inch, late 2009) OS X El Capitan Version 10.11.6. Is there any way to downgrade the Firefox install? I can't even see what previous version of Firefox I had before because I can't open the browser anymore. If anyone can help I would be super grateful. Thanks in advance!

Toutes les réponses (1)

more options

Firefox 78.15.0 ESR is the last version for Mac OS X 10.9/10.10/10.11 (distributionID: mozilla-mac-eol-esr1) and you will no longer receive updates.

Firefox 78.15.0 on the Mozilla CDN server:


Mac OS users on OS X 10.12/10.13/10.14 have been moved to the 115 ESR update channel since this platform no longer is supported, current releases require macOS 10.15 as a minimum.

Cela vous a-t-il été utile ?

Poser une question

Vous devez vous identifier avec votre compte pour répondre aux messages. Veuillez poser une nouvelle question, si vous n’avez pas encore de compte.